Thailand and Malaysia are said to be considering erecting a wall along their border in a bid to strengthen border security as well as to control transnational crimes and smuggling. A fence is already in place along some parts of their border stretching to 640km (398 miles).

Security has been a concern for both the countries in recent times with separatist insurgency rocking Thailand's deep south with bomb blasts. Experts have said Islamic militants have been using Malaysia's border as a base to plan and carry out attacks.

Besides, human trafficking and smuggling of illegal drugs and other goods along the Thai-Malay border have reportedly increased in the past few years, leading to some routes being blocked after Thai authorities launched a crackdown last year, Reuters reported.

"We both face security issues including the fight against terrorism, human trafficking and illegal smuggling, that is why we need to address these issues seriously," Thai Prime Minister Prayuth Chan-ocha said.

Malaysian Prime Minister Najib Razak said he considers security "a very important matter" and that he discussed the construction of the wall with his Thai counterpart.

"The matter is under consideration, but we need to determine the physical dimensions of the wall or fence as well as the sharing of the costs," he said.

It is not yet clear which country will bear the expenses for the border wall, but it is said to be similar to a plan that US Republican presidential candidate Donald Trump proposed. Trump said he would build a wall on the border between the US and its neighbour Mexico. His plan landed him in controversy as he also said he would get Mexico to pay for the wall.

"It is clear why Thailand is pursuing this wall," Srisompop Jitpiromsri from conflict monitor Deep South Watch told Reuters. "They view it as a necessary step to combat these groups that cause violence."

The group said more than 6,500 people were killed since 2004 by Muslim separatists in Thailand. The southern part of the country has been prone to attacks by so-called insurgent groups such as Barisan Revolusi Nasional.

Thailand is said to have annexed three provinces from its deep south that were once a part of an independent Malay Muslim sultanate until 1908.